The present disclosure relates to semiconductor device manufacturing, and more particularly, to methods for removing a high-quality material layer from a base substrate by spalling.
Devices that can be produced in thin-film form have three clear advantages over their bulk counterparts. First, by virtue of less material used, thin-film devices ameliorate the materials cost associated with device production. Second, low device weight is a definite advantage that motivates industrial-level effort for a wide range of thin-film applications. Third, if dimensions are small enough, devices can exhibit mechanical flexibility in their thin-film form. Furthermore, if the substrate from which a device layer is removed can be reused, additional fabrication cost reduction can be achieved.
Recent advances in spalling techniques now make it possible to remove, i.e., spall, a thin (typically less than 100 μm) material layer from an entire surface of base substrate with near-zero thickness direction kerf losses, and to do this multiple times on the same base substrate. The potential cost savings are enormous since (i) the thickness of the spalled material layer can be limited to the thickness needed for thin-film devices, and (ii) many spalled material layers may be derived from a single base substrate.
Further improvements in spalling are however needed which render spalling more efficient, controllable, and economical and thus more reliable for use in fabricating thin film semiconductor devices.